作者机构：
National Mobile Communications Research Laboratory,Southeast University,China;Hunan City University,
会议名称：
Progress in Electromagnetics Research Symposium 2008(2008年电磁学研究新进展学术研讨会)(PIERS 2008)
会议时间：
2008-03-24
会议地点：
杭州
会议论文集名称：
Progress in Electromagnetics Research Symposium 2008(2008年电磁学研究新进展学术研讨会)(PIERS 2008)论文集
摘要：
Using clustering and aggregation enables better resource allocation and helps im-prove power control in wireless sensor networks (WSNs). Nevertheless, repeated clustering would increase the overhead and reduce network lifetime. An energy-efficient data aggregation protocol based on static clustering (EDASC) is proposed to acquire good network performance. Simula-tion results show that this approach makes network lifetimes much longer and remarkably reduces control overhead.
摘要：
In wireless sensor networks (WSNs) application we sometimes only require single moment local field information, but traditional periodical all-network information collecting mode consumes much network resources. In order to satisfy Quality of Service (QoS) demands of information collection in wireless sensor networks, prolong network lifetime and minimize control overheads while insuring connectivity, a novel on-demand QoS protocol based on near static clustering (OQNSC) is proposed. This protocol employs a new near static clustering and cluster heads (CHs) rotation mechanism to aggregate information of collection fields on demand and selects maximum residual energy routing which meets QoS conditions for transmitting information among cluster heads. Simulation results show that OQNSC protocol can reduce control overheads effectively, prolong network lifetime significantly and improve the successful probability of information transmission.
作者机构：
School of Telecommunication Engineering Beijing University of Posts and Communications Beijing, Chin;Department of computer science & technology Hunan City University Yiyang , China
会议名称：
2007 IEEE International Conference on Automation and Lofistics
会议时间：
2007-08-18
会议地点：
山东济南
会议论文集名称：
2007 IEEE International Conference on Automation a
摘要：
A semi-blind algorithm to perform channel identification for multiple input multiple output(MIMO) systems in frequency and time-selective fading environments is proposed. It contains two steps:training and tracking.In training phase, improved Kalman filtering,namely robust Kalman filtering (RKF), is exploited to identify channel impulse response(CIR). After that,in tracking stage,the RKF and minimum mean-square error feedback decision equalizer (MMSE-DFE) cooperate to track the time-varying channel.The RKF recursions is presented and a closed-form solution for baud rate MIMO MMSE-DFE under perfect knowledge of CIR and correct past decisions conditions is derived. In addition, it regards unknown dc-offset due to zero intermediate frequency(IF) at the receiver as the mean of measurement noise, which is estimated as a byproduct through robust Kalman filters. Finally, it is compared with wellknown ones, such as least mean-square(LMS),recursive least square (RLS),Kalman filtering (KF).All these show that the proposal exhibits better performance.
作者机构：
School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing,C;Department of computer science & technology Hunan City University Yiyang,China
摘要：
A improved algorithm to perform channel estimation and equalization for multiple input multiple output(MIMO) systems in frequency and time-selective fading environments is put forward.It contains two steps:training and tracking.In training phase,improved kalman filtering,namly robust kalman filtering(RKF), is exploited to estimate channel impulse response(CIR). After that,in tracking stage,the RKF and minimum mean-square error feedback decision equalizer (MMSE-DFE) cooperate to track the time-varying channel.The RKF recursions is presented and a closed-form solution for baud rate MIMO MMSE-DFE under perfect knowledge of CIR and correct past decisions conditions is derived. In addition, it regards unknown dc-offset due to zero intermediate frequency(IF) at the receiver as the mean of measurement noise, which is estimated as a byproduct through robust Kalman filters.Finally,it is compared with well-known ones,such as least mean-square (LMS),recursive least square (RLS),kalman filtering (KF).All these show that the proposal exhibits better performance.
作者机构：
Institute of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan, 430070, Chin;Hunan City University, Yiyang, 413000, China
会议名称：
第三届中日岩土工程研讨会(Proceedings of the 3rd Sino-Japan Geotechnical Symposium)
摘要：
With the building of freeway, the problem of soft ground is becoming more and more protrusive and has been one of the key factors influencing project quality, project cycle and project cost. It has become a very important task to strengthen the research on the improvement of soft ground, which affects the development of traffic in China. In view of the incompleteness and uncertainty of information on soft ground improvement method,the decision model of the soft soil improvement methods based on multi-layer fuzzy is put forward. In this model, multi-layer structure model is set up, the weights of rule layer and index layer are given, the character index matrix of project layer is put forward and total ordering of the projects is decided. The actual examples results indicated that the decision model is reasonable, practical and convenient to use.
摘要：
A improved algorithm to perform channel estimation and equalization for multiple input multiple output(MIMO) systems in frequency and time-selective fading environments is put forward. lt contains two steps: training and tracking. In training phase, improved Kalman filtering, namely robust Kalman filtering(RKF), is exploited to estimate channel impulse response(CIR). After that, in tracking stage,the RKF and minimum mean-square error feedback decision equalizer (MMSE-DFE) cooperate to track the time-varying channel. The RKF recursions is presented and a closed-form solution for baud rate MIMO MMSE-DFE under perfect knowledge of CIR and correct past decisions conditions is derived. In addition, it regards unknown dc-offset due to zero intermediate frequency(IF) at the receiver as the mean of measurement noise, which is estimated as a byproduct through robust Kalman filters. Finally, it is compared with well-known ones,such as least mean-square (LMS), recursive least square (RLS), Kalman filtering (KF). All these show that the proposal exhibits better performance.
作者机构：
[Dafang Zhang] School of Computer & Communication, Hunan University, Changsha, Hunan, China;Department of Computer, Hunan City University, Changsha, Hunan, China;[Xuyu Xiang; Jiaohua Qin] School of Computer & Communication, Hunan University, Changsha, Hunan, China<&wdkj&>Department of Computer, Hunan City University, Changsha, Hunan, China
会议名称：
2007 International Conference on Convergence Information Technology (ICCIT 2007)
会议时间：
November 2007
会议地点：
Gwangju, Korea (South)
会议论文集名称：
2007 International Conference on Convergence Information Technology (ICCIT 2007)
摘要：
There are two general approaches to the longest common subsequence problem. The dynamic programming approach takes quadratic time but linear space, while the nondynamic-programming approach takes less time but more space. We propose a new implementation of the latter approach which seems to get the best for both time and space for the DNA application.
